busybox/libbb/setup_environment.c

/* vi: set sw=4 ts=4: */
/*
 * Copyright 1989 - 1991, Julianne Frances Haugh <jockgrrl@austin.rr.com>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of Julianne F. Haugh nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY JULIE HAUGH AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL JULIE HAUGH OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <stdio.h>
#include <errno.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <syslog.h>
#include <ctype.h>
#include "libbb.h"


#define DEFAULT_LOGIN_PATH      "/bin:/usr/bin"
#define DEFAULT_ROOT_LOGIN_PATH "/usr/sbin:/bin:/usr/bin:/sbin"

void setup_environment(const char *shell, int loginshell, int changeenv, const struct passwd *pw)
{
	if (loginshell) {
		const char *term;

		/* Change the current working directory to be the home directory
		 * of the user.  It is a fatal error for this process to be unable
		 * to change to that directory.  There is no "default" home
		 * directory.
		 * Some systems default to HOME=/
		 */
		if (chdir(pw->pw_dir)) {
			xchdir("/");
			fputs("warning: cannot change to home directory\n", stderr);
		}

		/* Leave TERM unchanged.  Set HOME, SHELL, USER, LOGNAME, PATH.
		   Unset all other environment variables.  */
		term = getenv("TERM");
		clearenv();
		if (term)
			xsetenv("TERM", term);
		xsetenv("HOME",    pw->pw_dir);
		xsetenv("SHELL",   shell);
		xsetenv("USER",    pw->pw_name);
		xsetenv("LOGNAME", pw->pw_name);
		xsetenv("PATH",   (pw->pw_uid ? DEFAULT_LOGIN_PATH : DEFAULT_ROOT_LOGIN_PATH));
	}
	else if (changeenv) {
		/* Set HOME, SHELL, and if not becoming a super-user,
		   USER and LOGNAME.  */
		xsetenv("HOME",  pw->pw_dir);
		xsetenv("SHELL", shell);
		if (pw->pw_uid) {
			xsetenv("USER",    pw->pw_name);
			xsetenv("LOGNAME", pw->pw_name);
		}
	}
}
1	/* vi: set sw=4 ts=4: */
2	/*
3	* Copyright 1989 - 1991, Julianne Frances Haugh <jockgrrl@austin.rr.com>
4	* All rights reserved.
5	*
6	* Redistribution and use in source and binary forms, with or without
7	* modification, are permitted provided that the following conditions
8	* are met:
9	* 1. Redistributions of source code must retain the above copyright
10	* notice, this list of conditions and the following disclaimer.
11	* 2. Redistributions in binary form must reproduce the above copyright
12	* notice, this list of conditions and the following disclaimer in the
13	* documentation and/or other materials provided with the distribution.
14	* 3. Neither the name of Julianne F. Haugh nor the names of its contributors
15	* may be used to endorse or promote products derived from this software
16	* without specific prior written permission.
17	*
18	* THIS SOFTWARE IS PROVIDED BY JULIE HAUGH AND CONTRIBUTORS ``AS IS'' AND
19	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21	* ARE DISCLAIMED. IN NO EVENT SHALL JULIE HAUGH OR CONTRIBUTORS BE LIABLE
22	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28	* SUCH DAMAGE.
29	*/
30
31	#include <stdio.h>
32	#include <errno.h>
33	#include <unistd.h>
34	#include <string.h>
35	#include <stdlib.h>
36	#include <syslog.h>
37	#include <ctype.h>
38	#include "libbb.h"
39
40
41
42	#define DEFAULT_LOGIN_PATH "/bin:/usr/bin"
43	#define DEFAULT_ROOT_LOGIN_PATH "/usr/sbin:/bin:/usr/bin:/sbin"
44
45	void setup_environment(const char shell, int loginshell, int changeenv, const struct passwd pw)
46	{
47	if (loginshell) {
48	const char *term;
49
50	/* Change the current working directory to be the home directory
51	* of the user. It is a fatal error for this process to be unable
52	* to change to that directory. There is no "default" home
53	* directory.
54	* Some systems default to HOME=/
55	*/
56	if (chdir(pw->pw_dir)) {
57	xchdir("/");
58	fputs("warning: cannot change to home directory\n", stderr);
59	}
60
61	/* Leave TERM unchanged. Set HOME, SHELL, USER, LOGNAME, PATH.
62	Unset all other environment variables. */
63	term = getenv("TERM");
64	clearenv();
65	if (term)
66	xsetenv("TERM", term);
67	xsetenv("HOME", pw->pw_dir);
68	xsetenv("SHELL", shell);
69	xsetenv("USER", pw->pw_name);
70	xsetenv("LOGNAME", pw->pw_name);
71	xsetenv("PATH", (pw->pw_uid ? DEFAULT_LOGIN_PATH : DEFAULT_ROOT_LOGIN_PATH));
72	}
73	else if (changeenv) {
74	/* Set HOME, SHELL, and if not becoming a super-user,
75	USER and LOGNAME. */
76	xsetenv("HOME", pw->pw_dir);
77	xsetenv("SHELL", shell);
78	if (pw->pw_uid) {
79	xsetenv("USER", pw->pw_name);
80	xsetenv("LOGNAME", pw->pw_name);
81	}
82	}
83	}